(a) Field of the Invention
The present invention relates to a method of manufacturing a semiconductor device. More particularly, the present invention relates to a method of forming a contact in a semiconductor device that can reduce or prevent deterioration of yield due to fallout particles.
(b) Description of the Related Art
Recently, as semiconductor integrated circuits have become more highly integrated, various methods for effective connection between wiring in a limited area have been proposed. Among them, a method enabling formation of multi-layered conductive lines in the integrated circuit has been widely used. According to such a multi-layer wiring method, a semiconductor chip may be manufactured at a very small size, since a space for wiring between devices may not be required.
A conventional method of forming a contact will hereinafter be described while referring to FIG. 1.
First, an interlayer insulating layer 102 composed of tetraethyl orthosilicate (TEOS), borophosphosilicate glass (BPSG), etc., is deposited on a semiconductor substrate 101 having a metal line layer thereon. After an etching mask (not shown) is formed on the interlayer insulating layer 102, a contact hole (not shown) is formed by selectively etching the interlayer insulating layer 102 using the mask.
Then, a barrier layer 104 is formed by the deposition of a titanium (Ti) film or a titanium (Ti)/titanium nitride (TiN) bilayer film by a sputtering method. Subsequently, a tungsten layer 106 is deposited by a chemical vapor deposition (CVD) method, and then is planarized by a chemical mechanical polishing (CMP) method, so the contact 108 that connects between metal lines in adjacent layers or between a metal line and an electrode is completed.
In such a method of forming a contact in a semiconductor device, fallout particles 110 are usually generated during the deposition of the barrier layer 104. Typically, such particles 110 are removed by a physical method, for example, by using a scrubber.
However, it is known that, according to such a conventional method using a scrubber, the particles are not always effectively removed. Therefore, the yield of semiconductor devices may not be achieved to a sufficiently high or desired level.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country or any other country to a person of ordinary skill in the art.